+
−"""some hooks and views to handle supervising of any data changes
+
−
+
−
+
−:organization: Logilab
+
−:copyright: 2001-2009 LOGILAB S.A. (Paris, FRANCE), all rights reserved.
+
−:contact: http://www.logilab.fr/ -- mailto:contact@logilab.fr
+
−"""
+
−__docformat__ = "restructuredtext en"
+
−
+
−from cubicweb import UnknownEid
+
−from cubicweb.selectors import none_rset
+
−from cubicweb.view import Component
+
−from cubicweb.common.mail import format_mail
+
−from cubicweb.server.hooksmanager import Hook
+
−from cubicweb.server.hookhelper import SendMailOp
+
−
+
−
+
−class SomethingChangedHook(Hook):
+
−    events = ('before_add_relation', 'before_delete_relation',
+
−              'after_add_entity', 'before_update_entity')
+
−    accepts = ('Any',)
+
−
+
−    def call(self, session, *args):
+
−        dest = self.config['supervising-addrs']
+
−        if not dest: # no supervisors, don't do this for nothing...
+
−            return
+
−        self.session = session
+
−        if self._call(*args):
+
−            SupervisionMailOp(session)
+
−
+
−    def _call(self, *args):
+
−        if self._event() == 'update_entity' and args[0].e_schema == 'CWUser':
+
−            updated = set(args[0].iterkeys())
+
−            if not (updated - frozenset(('eid', 'modification_date', 'last_login_time'))):
+
−                # don't record last_login_time update which are done
+
−                # automatically at login time
+
−                return False
+
−        self.session.add_query_data('pendingchanges', (self._event(), args))
+
−        return True
+
−
+
−    def _event(self):
+
−        return self.event.split('_', 1)[1]
+
−
+
−
+
−class EntityDeleteHook(SomethingChangedHook):
+
−    events = ('before_delete_entity',)
+
−
+
−    def _call(self, eid):
+
−        entity = self.session.entity(eid)
+
−        try:
+
−            title = entity.dc_title()
+
−        except:
+
−            # may raise an error during deletion process, for instance due to
+
−            # missing required relation
+
−            title = '#%s' % eid
+
−        self.session.add_query_data('pendingchanges',
+
−                                    ('delete_entity',
+
−                                     (eid, str(entity.e_schema),
+
−                                      title)))
+
−        return True
+
−
+
−
+
−def filter_changes(changes):
+
−    """
+
−    * when an entity has been deleted:
+
−      * don't show deletion of its relations
+
−      * don't show related TrInfo deletion if any
+
−    * when an entity has been added don't show owned_by relation addition
+
−    * don't show new TrInfo entities if any
+
−    """
+
−    # first build an index of changes
+
−    index = {}
+
−    added, deleted = set(), set()
+
−    for change in changes[:]:
+
−        event, changedescr = change
+
−        if event == 'add_entity':
+
−            entity = changedescr[0]
+
−            added.add(entity.eid)
+
−            if entity.e_schema == 'TrInfo':
+
−                changes.remove(change)
+
−                if entity.from_state:
+
−                    try:
+
−                        changes.remove( ('delete_relation',
+
−                                         (entity.wf_info_for[0].eid, 'in_state',
+
−                                          entity.from_state[0].eid)) )
+
−                    except ValueError:
+
−                        pass
+
−                    try:
+
−                        changes.remove( ('add_relation',
+
−                                         (entity.wf_info_for[0].eid, 'in_state',
+
−                                          entity.to_state[0].eid)) )
+
−                    except ValueError:
+
−                        pass
+
−                    event = 'change_state'
+
−                    change = (event,
+
−                              (entity.wf_info_for[0],
+
−                               entity.from_state[0], entity.to_state[0]))
+
−                    changes.append(change)
+
−        elif event == 'delete_entity':
+
−            deleted.add(changedescr[0])
+
−        index.setdefault(event, set()).add(change)
+
−    # filter changes
+
−    for eid in added:
+
−        try:
+
−            for change in index['add_relation'].copy():
+
−                changedescr = change[1]
+
−                # skip meta-relations which are set automatically
+
−                # XXX generate list below using rtags (category = 'generated')
+
−                if changedescr[1] in ('created_by', 'owned_by', 'is', 'is_instance_of',
+
−                                      'from_state', 'to_state', 'wf_info_for',) \
+
−                       and changedescr[0] == eid:
+
−                    index['add_relation'].remove(change)
+
−                # skip in_state relation if the entity is being created
+
−                # XXX this may be automatized by skipping all mandatory relation
+
−                #     at entity creation time
+
−                elif changedescr[1] == 'in_state' and changedescr[0] in added:
+
−                    index['add_relation'].remove(change)
+
−
+
−        except KeyError:
+
−            break
+
−    for eid in deleted:
+
−        try:
+
−            for change in index['delete_relation'].copy():
+
−                fromeid, rtype, toeid = change[1]
+
−                if fromeid == eid:
+
−                    index['delete_relation'].remove(change)
+
−                elif toeid == eid:
+
−                    index['delete_relation'].remove(change)
+
−                    if rtype == 'wf_info_for':
+
−                        for change in index['delete_entity'].copy():
+
−                            if change[1][0] == fromeid:
+
−                                index['delete_entity'].remove(change)
+
−        except KeyError:
+
−            break
+
−    for change in changes:
+
−        event, changedescr = change
+
−        if change in index[event]:
+
−            yield change
+
−
+
−
+
−class SupervisionEmailView(Component):
+
−    """view implementing the email API for data changes supervision notification
+
−    """
+
−    __select__ = none_rset()
+
−    id = 'supervision_notif'
+
−
+
−    def recipients(self):
+
−        return self.config['supervising-addrs']
+
−
+
−    def subject(self):
+
−        return self.req._('[%s supervision] changes summary') % self.config.appid
+
−
+
−    def call(self, changes):
+
−        user = self.req.actual_session().user
+
−        self.w(self.req._('user %s has made the following change(s):\n\n')
+
−               % user.login)
+
−        for event, changedescr in filter_changes(changes):
+
−            self.w(u'* ')
+
−            getattr(self, event)(*changedescr)
+
−            self.w(u'\n\n')
+
−
+
−    def _entity_context(self, entity):
+
−        return {'eid': entity.eid,
+
−                'etype': entity.dc_type().lower(),
+
−                'title': entity.dc_title()}
+
−
+
−    def add_entity(self, entity):
+
−        msg = self.req._('added %(etype)s #%(eid)s (%(title)s)')
+
−        self.w(u'%s\n' % (msg % self._entity_context(entity)))
+
−        self.w(u'  %s' % entity.absolute_url())
+
−
+
−    def update_entity(self, entity):
+
−        msg = self.req._('updated %(etype)s #%(eid)s (%(title)s)')
+
−        self.w(u'%s\n' % (msg % self._entity_context(entity)))
+
−        # XXX print changes
+
−        self.w(u'  %s' % entity.absolute_url())
+
−
+
−    def delete_entity(self, eid, etype, title):
+
−        msg = self.req._('deleted %(etype)s #%(eid)s (%(title)s)')
+
−        etype = display_name(self.req, etype).lower()
+
−        self.w(msg % locals())
+
−
+
−    def change_state(self, entity, fromstate, tostate):
+
−        msg = self.req._('changed state of %(etype)s #%(eid)s (%(title)s)')
+
−        self.w(u'%s\n' % (msg % self._entity_context(entity)))
+
−        self.w(_('  from state %(fromstate)s to state %(tostate)s\n' %
+
−                 {'fromstate': _(fromstate.name), 'tostate': _(tostate.name)}))
+
−        self.w(u'  %s' % entity.absolute_url())
+
−
+
−    def _relation_context(self, fromeid, rtype, toeid):
+
−        _ = self.req._
+
−        session = self.req.actual_session()
+
−        def describe(eid):
+
−            try:
+
−                return _(session.describe(eid)[0]).lower()
+
−            except UnknownEid:
+
−                # may occurs when an entity has been deleted from an external
+
−                # source and we're cleaning its relation
+
−                return _('unknown external entity')
+
−        return {'rtype': _(rtype),
+
−                'fromeid': fromeid,
+
−                'frometype': describe(fromeid),
+
−                'toeid': toeid,
+
−                'toetype': describe(toeid)}
+
−
+
−    def add_relation(self, fromeid, rtype, toeid):
+
−        msg = self.req._('added relation %(rtype)s from %(frometype)s #%(fromeid)s to %(toetype)s #%(toeid)s')
+
−        self.w(msg % self._relation_context(fromeid, rtype, toeid))
+
−
+
−    def delete_relation(self, fromeid, rtype, toeid):
+
−        msg = self.req._('deleted relation %(rtype)s from %(frometype)s #%(fromeid)s to %(toetype)s #%(toeid)s')
+
−        self.w(msg % self._relation_context(fromeid, rtype, toeid))
+
−
+
−
+
−class SupervisionMailOp(SendMailOp):
+
−    """special send email operation which should be done only once for a bunch
+
−    of changes
+
−    """
+
−    def _get_view(self):
+
−        return self.session.vreg.select_component('supervision_notif',
+
−                                                  self.session, None)
+
−
+
−    def _prepare_email(self):
+
−        session = self.session
+
−        config = session.vreg.config
+
−        uinfo = {'email': config['sender-addr'],
+
−                 'name': config['sender-name']}
+
−        view = self._get_view()
+
−        content = view.render(changes=session.query_data('pendingchanges'))
+
−        recipients = view.recipients()
+
−        msg = format_mail(uinfo, recipients, content, view.subject(), config=config)
+
−        self.to_send = [(msg, recipients)]
+
−
+
−    def commit_event(self):
+
−        self._prepare_email()
+
−        SendMailOp.commit_event(self)